package cn.ztelovecly.springboot.framework.util;

public class UrlUtil {
    /**
     * 获取URL请求资源的类型
     *
     * @param url 请求URL
     * @return 资源类型
     */
    public static String getSuffix(String url) {
        String ext;
        url = url.replace("http://", "");
        url = url.replace("https://", "");
        url = url.substring(url.indexOf("/"), url.length());

        if (url.contains("?")) {
            url = url.substring(0, url.indexOf("?"));
        }

        if (url.lastIndexOf(".") == -1) {
            ext = "";
        } else {
            ext = url.substring(url.lastIndexOf(".") + 1);
        }

        return ext;
    }

    /**
     * 截取域名信息。去除协议名、资源名、端口号、参数等信息。
     *
     * @param url 完整的URL
     * @return 该URL对应的域名
     */
    public static String getDomain(String url) {
        // 过滤协议名
        url = url.replace("http://", "").replace("https://", "");

        // 去除端口号以后的内容
        if (url.contains(":")) {
            url = url.substring(0, url.indexOf(":"));
        }
        // 去除目录
        if (url.contains("/")) {
            url = url.substring(0, url.indexOf("/"));
        }
        return url;
    }

    public static String escape(String src) {
        int i;
        char j;
        StringBuilder tmp = new StringBuilder();
        tmp.ensureCapacity(src.length() * 6);
        for (i = 0; i < src.length(); i++) {
            j = src.charAt(i);
            if (Character.isDigit(j) || Character.isLowerCase(j)
                    || Character.isUpperCase(j))
                tmp.append(j);
            else if (j < 256) {
                tmp.append("%");
                if (j < 16)
                    tmp.append("0");
                tmp.append(Integer.toString(j, 16));
            } else {
                tmp.append("%u");
                tmp.append(Integer.toString(j, 16));
            }
        }
        return tmp.toString();
    }

    public static String unescape(String src) {
        StringBuilder tmp = new StringBuilder();
        tmp.ensureCapacity(src.length());
        int lastPos = 0, pos = 0;
        char ch;
        while (lastPos < src.length()) {
            pos = src.indexOf("%", lastPos);
            if (pos == lastPos) {
                if (src.charAt(pos + 1) == 'u') {
                    ch = (char) Integer.parseInt(src
                            .substring(pos + 2, pos + 6), 16);
                    tmp.append(ch);
                    lastPos = pos + 6;
                } else {
                    ch = (char) Integer.parseInt(src
                            .substring(pos + 1, pos + 3), 16);
                    tmp.append(ch);
                    lastPos = pos + 3;
                }
            } else {
                if (pos == -1) {
                    tmp.append(src.substring(lastPos));
                    lastPos = src.length();
                } else {
                    tmp.append(src.substring(lastPos, pos));
                    lastPos = pos;
                }
            }
        }
        return tmp.toString();
    }

}
